X-ray and Radio go ‘Hand in Hand’ in New Image
In 2009, the NASA X -ray observatory published a captivating image: a pulsar and its surrounding nebula which is in the shape of a hand.
Since then, astronomers have used Chandra and other telescopes to continue to observe this object. From now on, the new radio data from Australia Telescope Compact Array (ACCA) have been combined with Chandra X -ray data to provide a new view of this exploded star and its environment, to help understand its particular properties and forms.
In the center of this new image is the Pulsar B1509-58, a neutron star which is running quickly which has only about 12 miles in diameter. This small object is responsible for the production of a complex nebula (called MSH 15-52) which covers more than 150 light years, or around 900 billions of Miles. The nebula, which is produced by energetic particles, resembles a human hand with a palm and extensive fingers pointing up to the right in the X -rays.
The collapse of a massive star created the pulsar when a large part of the star crashed inwards once it has burned its lasting nuclear fuel. An explosion that followed sent the outer layers of the star to the outside in space like a supernova.
The pulsar turns towards almost seven times per second and has a strong magnetic field, about 15 billions of times stronger than that of the earth. The rapid rotation and the strong magnetic field make B1509-58 B1509-58 one of the most powerful electromagnetic generators in the galaxy, which allows it to chase an energetic wind of electrons and other particles far from the pulsar, creating the nebula.
In this new composite image, ACCA radio data (represented in red) were combined with chandra X -rays (illustrated in blue, orange and yellow), as well as an optical image of gas hydrogen (gold). The overlap areas between X-ray and radio data in MSH 15-52 show purple. The optical image shows stars in the field of vision as well as parts of the supernova debris, the RCW 89 supernova. A labeled version of the figure shows the main characteristics of the image.
ACCA radio data is now revealing complex filaments that are aligned with the Magnetic fields of the nebula, shown by short and straight white lines in an additional image. These filaments could result from the collision of the wind of the pulsar particles with the debris of the supernova.
By comparing the radio and radiographic data, the researchers have identified key differences between the sources of the two types of light. In particular, certain characteristics of prominent X -ray, including the jet to the bottom of the image and the interior parts of the three “fingers” up, are not detected in the radio waves. This suggests that the very energetic particles escape from a shock wave – similar to the sound arrow of a supersonic plane – near the pulsar and moving along the magnetic field lines to create the fingers.
Radio data also show that the RCW 89 structure is different from the typical young remains of supernova. A large part of the radio program is uneven and closely corresponds to the tufts of X -ray and optical emission. It also extends far beyond the emission of X-rays. All these characteristics support the idea that RCW 89 collides with a dense cloud of hydrogen nearby.
However, researchers do not fully understand everything that the data shows them. A perplexed area is the net limit of X -ray emission at the top right of the image which seems to be the breath wave of the supernova – see the labeled function. Supernova blast waves are generally shiny in radio waves for young remains of supernova like RCW 89, it is therefore surprising for researchers that there is no radio signal at the limit of X -rays.
MSH 15–52 and RCW 89 show many unique features that are not found in other young sources. However, there are still many open questions concerning the training and evolution of these structures. Additional work is necessary to better understand the complex interaction between the pulsar wind and the supernova debris.
An article describing this work, led by Shumeng Zhang of the University of Hong Kong, with the co-authors Stephen Cy Ng of the University of Hong Kong and Niccolo ‘Bucciantini of the Italian National Institute for Astrophysics, was published in the Astrophysical Journal and is available at https://iopscience.iop.org/article/10.3847/1538-4357/adf333.
The Marshall Space Flight Center of NASA in Huntsville, in Alabama, manages the Chandra program. The X-ray center of Smithsonian Astrophysical Observatory controls the scientific operations of Cambridge, Massachusetts, and the flight operations from Burlington, Massachusetts.
Find out more about the Chandra’s radiography observatory and its mission here:
https://chandra.si.edu
This version presents a composite image of a nebula and a pulsar which strongly resembles a cosmic hand reaching a neon red cloud.
The neon red cloud is near the top of the image, just in our center right. The ruptures in the cloud reveal strands intertwined with gold resembling spider ewebs or a trellis sub-structure. This cloud is the remains of the supernova that formed the pulsar in the heart of the image. The pulsar, a neutron star which quickly turns at only 12 miles in diameter, is far too small to be seen in this image, which represents a region of space in 150 light years.
The lower half of the image is dominated by a massive blue hand which heads towards the pulsar and supernova cloud. It is a complex nebula called MSH 15-52, an energetic wind of electrons and other particles distant from the pulsar. The resemblance to one hand is undeniable. Inside the nebula, the streaks and whirlpools of blue goes from pale to the navy, evoking a medical radiography, or the desire hand of a giant cosmic ghost.
The hand and the nebula are placed against the darkness of the space, surrounded by dozens of brilliant golden spots. At the bottom left, a golden hydrogen cloud extends beyond the edges of the image. In this composite, gold represents optical data; Red represents Radio ATCA data; And blue, orange and yellow represent Chandra X -ray data. When the blue hand of the nebula rides the radio data in red, the fingers seem foggy and purple.
Megan Watzke
Chandra X X -ray center
Cambridge, mass.
617-496-7998
mwatzke@cfa.harvard.edu
Corinne Beckinger
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
Corinne.m.beckinger@nasa.gov
